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1.
Improved Hardy inequality with double singular kernel in bounded, star-shaped domains \(\Omega \subset R^n\) is proved. The case of singularity at an interior point and on the boundary of the domain is considered. The Hardy constant is optimal and the inequality is sharp due to the additional term.  相似文献   
2.
The effect of simultaneous substitution of a fluctuating cation and a divalent cation in LaMnO3 perovskite modifies the properties of the material to exhibit large valence colossal magnetoresistance (CMR) effect. A good example of these properties is (La1−2x Pr x Ca x )MnO3 (LPCMO) type CMR material. In this communication it is reported that, with the increase in x (for x=0.1, 0.15, 0.2), the T c varies between 100 and 120 K with improvisation in metal-insulator transition. Interestingly, resistance increases with x from few hundred ohms to few kilo ohms with corresponding decrease in the unit cell volume. The results of the studies using X-ray diffraction (XRD), electrical resistivity, magnetoresistance and ac susceptibility measurements on LPCMO samples for understanding the structural, transport and magnetic properties are discussed in detail.  相似文献   
3.
The synthesis of the rare bioactive phenylpropanoid ester known as cimiracemate B (1) from black cohosh, Cimicifuga racemosa, is described. The procedure employs a coupling method using 1, l'-carbonyldiimidazole and methyltrifluoromethanesulfonate as coupling reagents in the presence of N-methylmorpholine.  相似文献   
4.
Molecular beam electric resonance spectroscopy has been used to measure the l-type doubling transitions in carbonyl sulfide. Transitions in J = 4 to J = 20 have been observed for the (0220) vibrational state and for J = 1 and J = 2 for the (0310) state. The data has been analyzed to give the v = 2 energy separation EΔ0 - EΣ0 = ?5.7861(2) + 8.36(1) × 10?5 J(J + 1) cm?1, and the vibrational dependence of q to be 86.52(9)(v2 + 1) KHz. The dipole moment of the (0220) vibrational state is 0.6936(3) D.  相似文献   
5.
We prove Hardy-type inequality with weight singular at ${0 \in \Omega}$ in the class of functions which are not zero on the boundary ${\partial \Omega}$ . The Hardy constant is optimal and the inequality is sharp due to the additional boundary term.  相似文献   
6.
Priyadarshini  S.  Guru  P. S.  DS  R.  Dash  S. 《Kinetics and Catalysis》2019,60(2):147-154
Kinetics and Catalysis - Kinetic study of cholesterol oxidation has been studied using a series of N-cetylpicolinium dichromates (CPDC), a class of phase transfer oxidants, in acetic acid medium...  相似文献   
7.
A Hardy-type inequality with singular kernels at zero and on the boundary ?Ω is proved. Sharpness of the inequality is obtained for Ω= B 1(0).  相似文献   
8.
DS Agosta  AV Skripov 《哲学杂志》2013,93(2):299-306
Resonant ultrasound spectroscopy was used to measure the elastic constants of bcc Ta0.33V0.67 over the temperature range 3.5–300?K; the results were compared to earlier measurements on C15 TaV2. The temperature dependence of the polycrystalline shear modulus is completely different in the two phases; that of the bcc phase decreases with temperature whereas that of the C15 phases increases in an anomalous fashion. This difference is consistent with a model involving doubly-degenerate levels at the X point of the Brillouin zone in the C15 phase with the Fermi level lying near the doubly degenerate level. This model accounted for the unusual behaviour of the C15 phase. Debye temperatures were determined from the ultrasonic measurements: 295?K for the C15 phase and 315?K for the bcc phase.  相似文献   
9.
Th electromagnetic field produced by a magnetic dipole in thepresence of a perfectly conducting cone of arbitrary cross-sectionis determined. The solution is used to find out how a currenton the cone travelling towards the apex is reflected. Some valuesof the reflection coefficient are calculated. In particular,it is shown that there is a sort of resonance with the reflectionincreasing significantly as the cone approaches a plane.  相似文献   
10.
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